We propose to develop useful syntheses of dodecahedrane and the heterododecahedranes and their derivatives. Our objective is to obtain multi-gram quantities so as to permit detailed studies of the fundamental properties of these highly symmetric and hence "simple" systems. Our studies will establish basic reference points about intramolecular interactions and will allow a thorough evaluation of the meaningfulness of the theoretical calculations already done on such systems. This will help put such things into proper perspective. Our synthetic work will provide new methods and methodology for the preparation of difficult carbon systems and push outward the frontiers of organic structural types -- making known new, unusual, non-naturally occurring systems. These will be evaluated at DR&D for antitumor activity.